mi·o·sis

also my·o·sis (mī-ō′sĭs)

n. pl. mi·o·ses (-sēz) also my·o·ses

Constriction of the pupil of the eye, resulting from a normal response to an increase in light or caused by certain drugs or pathological conditions.

[Greek mūein, to close the eyes + -osis.]

American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

miosis

(maɪˈəʊsɪs) or

myosis

n, pl -ses (-siːz)

1. (Pathology) excessive contraction of the pupil of the eye, as in response to drugs

2. (Biology) a variant spelling of meiosis¹

[C20: from Greek muein to shut the eyes + -osis]

miotic, myotic adj, n

Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

mi•o•sis

or my•o•sis

(maɪˈoʊ sɪs)

n.

excessive constriction of the pupil of the eye.

Compare mydriasis.

[1810–20; variant of myosis < Greek mý(ein) to shut (the eyes) + -osis]

miosis, myosis

abnormal constriction of the pupil of the eye, caused by drugs or illness. Cf. mydriasis. — miotic, myotic, adj.

See also: Eyes

ThesaurusAntonymsRelated WordsSynonymsLegend:

Noun	1.	miosis - (genetics) cell division that produces reproductive cells in sexually reproducing organisms; the nucleus divides into four nuclei each containing half the chromosome number (leading to gametes in animals and spores in plants) meiosis, reduction division genetic science, genetics - the branch of biology that studies heredity and variation in organisms anaphase - the stage of meiosis or mitosis when chromosomes move toward opposite ends of the nuclear spindle cell division, cellular division - the process in reproduction and growth by which a cell divides to form daughter cells cytokinesis - organic process consisting of the division of the cytoplasm of a cell following karyokinesis bringing about the separation into two daughter cells karyokinesis - organic process consisting of the division of the nucleus of a cell during mitosis or meiosis metaphase - the second stage of meiosis nondisjunction - meiosis in which there is a failure of paired homologous chromosomes to separate; results in an abnormal number of chromosomes in the daughter cells prophase - the first stage of meiosis segregation - (genetics) the separation of paired alleles during meiosis so that members of each pair of alleles appear in different gametes telophase - the final stage of meiosis when the chromosomes move toward opposite ends of the nuclear spindle
	2.	miosis - reflex contraction of the sphincter muscle of the iris in response to a bright light (or certain drugs) causing the pupil to become smaller light reflex, pupillary reflex, myosis inborn reflex, innate reflex, instinctive reflex, physiological reaction, reflex, reflex action, reflex response, unconditioned reflex - an automatic instinctive unlearned reaction to a stimulus

Translations

mi·o·sis

n. miosis, contracción excesiva de la pupila.

English-Spanish Medical Dictionary © Farlex 2012

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References in periodicals archive

Diclofenac eye drops are used to prevent miosis in and treat inflammations after cataract extraction, treat non-infectious eye inflammations caused or not caused by surgeries, prevent postoperative inflammatory reactions and the formation of cystoid macular edema, promote the formation of filtration blebs after glaucoma filtering surgeries, and treat allergic conjunctivitis.

China Diclofenac Investigation Market Report, 2019-2023

for use during cataract surgery or intraocular lens (IOL) replacement to maintain pupil size by preventing intraoperative miosis (pupil constriction) and to reduce postoperative ocular pain.

Omeros to Present at the 2019 Wedbush PacGrow Healthcare Conference

The company's drug product Omidria (phenylephrine and ketorolac intraocular solution) 1% / 0.3% is marketed in the US for use during cataract surgery or intraocular lens replacement to maintain pupil size by preventing intraoperative miosis (pupil constriction) and to reduce postoperative ocular pain.

Omeros and Lonza Enter Long-Term Manufacturing Agreement for Commercial Supply of Narsoplimab

* When combined with fentanyl, heroin becomes 50 to 100 dmes more potent, resulting in a subjective high with exaggerated central nervous system depression manifesting as lethargy, miosis, and respiratory depression.

CASE REPORT

Overstimulation of the parasympathetic axons that innervate the iris sphincter muscle initiates painful miosis, even with mild nerve-agent vapor exposures.

Chemical Warfare: Nerve Agents

Clinical features of this syndrome include ptosis, miosis, and anhidrosis.

Syndromes in maxillofacial injuries

Contralateral miosis may be a consequence of direct stimulation of the optic nerve through the thin interorbital septum.

Trauma-Induced Uveitis and Free Air in the Anterior Chamber of Three Eastern Screech Owls (Megascops asio)

Omidria, approved and commercially available in the U.S., is also approved in the European Union for use in cataract and lens replacement surgery to maintain mydriasis, prevent miosis and to reduce postoperative eye pain.

Omeros initiates sales of Omidria in Europe, satisfies 'sunset clause'

On admission, neurologic physical examination showed dysarthria, bilateral miosis, slow pupillary light reflex, weakened pharyngeal reflex, reduction in the right limb strength (right arm strength grade 4/5, right leg strength grade 2/5), and hemihypesthesia of the right limb.

Unilateral Isolated Basal Vein Thrombosis Associated with Deep Cerebral Venous Infarction

Dr Mirzayanov said the first sign was miosis - excessive pupil constriction.

POISON CITY OF FEAR; THE NOVICHOK SCANDAL: SECOND INCIDENTPolice hunt for more contaminated material Family fear Dawn is now on 'brink of death'